BCL6 and diffuse large B-cell lymphoma: Immunohistochemistry (Fig. 3): Positive: CD20, CD19, CD10, Bcl-6 (80%), Bcl-2 (90%), MUM-1, C-Myc (20%), CD5 (partial); Negative: S-100, SOX-10, EMA, CKpanWe, ALK, CyclinD1, TdT; Proliferation/Apoptosis: Ki-67 (80% in hotspots), P53 (wild-type); T-cell Marker: CD3 (background T-cells+); Diagnosis: Aggressive B-cell lymphoma, consistent with diffuse large B-cell lymphoma (DLBCL), germinal center B-cell(GCB).[3]